Another Exact Ground State of a 2D Quantum Antiferromagnet

TL;DR

This paper identifies a new exact dimer ground state in a 2D quantum antiferromagnet on the maple-leaf lattice, highlighting conditions for its stability and its uniqueness among 2D lattice models.

Contribution

It introduces a novel exactly solvable model with a dimer ground state on the maple-leaf lattice, expanding the class of known 2D quantum antiferromagnet solutions.

Findings

Exact dimer ground state on maple-leaf lattice

Coupling anisotropy stabilizes the dimer state

Only this model and Shastry-Sutherland have exact dimer ground states in 2D uniform tilings

Abstract

We present the exact dimer ground state of a quantum antiferromagnet on the maple-leaf lattice. A coupling anisotropy for one of the three inequivalent nearest-neighbor bonds is sufficient to stabilize the dimer state. Together with the Shastry-Sutherland Hamiltonian, we show that this is the only other model with an exact dimer ground state for all two-dimensional lattices with uniform tilings.